Gate for pneumatic cool-cleaning apparatus



March 6, 1934. A. ALLEN GATE FOR PNEUMATIC COAL CLEANING APPARATUS Filed Aug. 7, 1930 2 Sheets-Sheet l r-ngys.

March 6, 1934. ALLEN 1,949,734

GATE FOR PNEUMATIC COAL CLEANING APPARATUS Filed Aug. 7, 1930 2 Sheets-Sheet 2 :8 Andra/a A/ZPIZ i of the table.

Patented Mar. 6, 1934 UNETED STATES FATE OFFICE GATE FOR PNEUMZATIC COOL-CLEANING APPARATUS Andrews Allen, Glencoe, 111., assignor, by mesne assignments, to Peale-Davis Company, Wilmington, Del., a corporation of Delaware Application August 7, 1930, Serial No. 473,583

10 Claims.

., for separating coal or similar material from heavier refuse material, the mixed coal and refuse is fed onto one end of a table in a substantially even layer, the table being mechanically actuated so as to advance the materials longitudinally The supporting deck of the table is divided into a plurality of diagonally extending parallel zones. Air under pressure is projected upwardly through the deck so as to form an air cushion for supporting the lighter materials, the air pressure being greatest in those zones at the supply end of the table and gradually diminishing toward the delivery end of the table. The air pressure is such that in any one zone, coal of a certain size will be supported above the deck by the air pressure, whereas heavier refuse of a similar size will be unsupported by this air and will rest upon the upper surface of the deck. A plurality of diagonally extending riiiles or projecting ledges positioned on the supporting deck serve to direct the heavier materials which are unsupported by the air cushion toward one side of the table Where outlet gates permit this heavier refuse material to be expelled into collection chutes. The heights of these gate openings are so graduated that each opening will for these gate openings to become clogged, particularly by larger pieces of coal which attempt to go out through the opening and which effectively block the opening so as to prevent the passage of the refuse. According to this invention, a

1 gate is provided which is given a slight up and down motion across the upper portion of the outlet opening. This moving gate tends to keep the mass of coal and other material back of the gate opening in constant motion, thus permitting the refuse to work its way past and escape through the opening. The bottom edge of the gate is also sharpened to a moderately sharp edge, so that any pieces or" material which become actually caught in the opening will be cut down or split so as to prevent clogging of the opening. A self-cleaning gate opening is thus provided.

The general object of this invention is to provide a new and improved gate for a pneumatic coal cleaning apparatus, as briefly described hereinabove and as disclosed more in detail in the specifications which follow.

Another object is to provide a vertically movable gate member in combination with means actuated by the movement of the table for imparting movement to the gate.

Another object is to provide a gate member having a lower cutting edge, and means for reciprocating said gate vertically above the upper portion of the gate opening.

Another object is to provide means accessible iroin outside the separating chamber above the table for adjusting the vertical path of movement of the gate so as to vary the effective'size of the gate opening.

Another object is to provide improved means for varying the amplitude of the vertical movement of the gate.

Another object is to provide improved means for supporting the gate for vertical movement adjacent one of the gate openings.

Other objects and advantages of this invention will be more apparent from the following detailed description of one approved form of apparatus constructed according to the principles of this invention.

In the accompanying drawings:

Fig. 1 is a side elevation, largely diagrammatic, of a portion of the coal-cleaning apparatus. 7

Fig. 2 is a transverse vertical section, partially broken away, the view being taken substantially on the line 2--2 of Fig. 3.

Fig. 3 is a side elevation of one of the improved gates and the operating mechanism therefor, the view being taken from above the table looking toward one side thereof.

Fig. 4 is a partial horizontal section, taken substantially on the line 4-4 of Fig. 8.

Fig. 5 is a partial vertical section, taken substantially on the line 5-5 of Fig. 3.

Fig. 6 is a side elevation, on a larger scale, of

the supporting and adjusting mechanism for varying the vertical path of travel of the gate.

Fig. 7 is a plan view of the mechanism shown in Fig. 6.

Fig. 8 is a detail vertical section, illustrating the method of operation of the improved selfcleaning gate.

In order that the particular improvements of this present invention may be better understood, we will first briefly describe an air-cleaning system for coal or similar material, such as is now known and used. The separating table indicated as an entirety at 1 is mounted on a plurality of supporting links 2, and is reciprocated by means of a pitman 3 connected with a crank disc 4 driven by a motor mechanism, indicated at 5. As a. result, the table is given a succession of upward and forward reciprocations, so that material deposited on the left hand end of the table (Fig. 1) from the bin 6 and delivery chute 7 will be caused to travel longitudinally of the table in the direction indicated by the arrow a.

The table 1 comprises an upper or zoning deck 8 and a lower deck 9 separated by a plurality of vertical partitions 10 which separate the several zones and support the upper and lower decks. These zones extend diagonally of the table, as do also the riflles 11 which are mounted on the upper surface of zoning deck 8. The upper deck 8 comprises a lower supporting and strengthening layer of wire mesh 12, and an upper layer 13 of so-called zoning cloth usually in the form of a thin brass sheet formed with a series of spaced perforations 14. The amount and pressure of the air permitted to pass upwardly through the deck 8 in any one zone is determined by the size of the perforations 14, larger perforations 14 being used adjacent the lefthand or supply end of the table (Fig. 1) whereas smaller perforations will be used adjacent the delivery end of the table where decreased air pressure is required. It is to be understood that the sizes of these perforations 14 will be graduated from end to end of the table, that is, there will be several different sizes used in accordance with the air pressure desired in the different zones. The lower deck 9, which may conveniently be made of sheet metal, is provided with a plurality of openings 15, through which, air under pressure passes upwardly into the several zones from the common air duct 16 which extends beneath the entire table and is supplied with air under pressure from a fan 17 or other suitable source of supply. The amount of air supplied to each zone may be regulated in accordance with the requirements of that zone by closing a certain proportion of the openings 15 by means of plugs 18. At the end of the table where the greater air pressure, and consequently greater supply of air is required, fewer plugs 18 are used than at the delivery end of the table where the air pressure is decreased.

The riilies 11 are preferably in the form of rather small angle bars, each comprising a horizontal flange secured to the upper surface of the table and an upstanding flange which projects upwardly a sufiicient distance to engage the pieces of material which are too heavy to be supported by the air cushion in any particular zone and directs such material toward the gate opening provided at one side of the table.

As best shown in Fig. 2, the table 1 is inclined toward one side at a small angle, the riilles 11 being diagonally disposed so as to direct the material on the table toward the higher side of the table, as indicated at the left in Fig. 2. An imperforate vertical side wall 19 is provided at the low side of the table for directing the finer grades of material longitudinally of the table. The side wall 20 at the opposite or higher side of the table is provided with a plurality of exit or gate openings 21, one at the end of each zone, through which refuse is expelled into the chutes indicated at 22. These openings 21 are of gradually decreasing height lengthwise of the table, and adapted to permit the exit of a certain size of refuse without permitting the escape of coal, all as will be hereinafter more apparent.

Suitable flexible side walls or curtains 23 are secured between the rigid side walls 19 and 20 of table 1 and fixed upper supporting members or beams 24 so as to prevent the escape of dust or fine material from the separating chamber 23 of the above table 1.

Movable gates 25 (which are the particular subject matter of this invention and will be described more in detail hereinafter) are located, one inside of and above each gate opening 21. The openings 21 in the side wall 20 are each somewhat higher than the desired effective height of the outlet passage, the exact height of this passage being determined by the positioning of the lower sharpened edge 26 of gate 25.

Referring now more particularly to Fig. 8, the principle of operation of a separating system of this type will first be briefly described. The air under pressure directed upwardly, as indicated by the arrows and passing through the holes 14 in the zoning deck will form an air cushion which will tend to support all material under a certain weight above the surface of the table. In Fig. 8, the pieces of coal are indicated by light shading, whereas the heavier refuse material is indicated by heavier shading. The air pressure in any particular zone will be so adjusted that pieces or lumps of coal of the size A will be supported above the table by the air cushion, whereas pieces of the heavier refuse B of similar size will be too heavy to be supported by this air cushion and will rest upon the zoning deck. Smaller pieces of refuse, such as C, will also be supported by the air cushion (as of course will all smaller pieces of both coal and refuse) but larger pieces of coal, such as indicated at D, will be too heavy to be supported by the air cushion and will also rest upon the zoning deck. The gate opening 21 will be adjusted to such a size that the masses of refuse B can pass through the opening, whereas the larger pieces of coal D, also unsupported by the air cushion in that zone, will be too large to pass through the opening. Due to the movement of the table, these larger pieces of coal will find their way over into the next zone, together with the smaller pieces of coal and refuse A and C. In the next zone a lower air pressure will be used and a smaller gate opening, so that a smaller size of refuse will be eliminated in a similar manner. The net result is to gradually eliminate all of the refuse, starting with the larger sizes and ending with the smaller sizes, whereas all of the coal will be retained on the table and collected in a suitable manner at the delivery end of the table.

In systems of this type, as heretofore known, where gate openings 21 of a fixed size have been used, there has been a tendency for the openings to clog, particularly by the larger pieces of coal which attempt to pass through the opening and sometimes become clogged therein so as to block the opening and prevent the refuse from passing out. According to the present invention, the movable gate members 25 which are positioned across the upper portion of openings 21, keep the material behind the openings in constant motion and efiectively prevent clogging of the opening, as will hereinafter be apparent. The gate 25 is in the form of a fiat bar of greater length than the outlet opening 21 (see Fig. 3) and adapted to fit closely against the inner surface of side wall 20. One end of the gate is pivotally mounted at 27 between the adjacent side wall 26 and a bracket 23, which is attached at its upper end, as at 29, to the side wall and thence bowed outwardly to enclose the end of the gate member. The brackets 28 may be made of standard length and provided with a series of pivot openings 30 in any one of which the pivoted end of gate 25 may be mounted, since some of the gates must be mounted higher above the table than others, due to the varying sizes of the gate openings used in the difierent zones. The opposite or ree end 31 of gate 25 is pivotally connected by means of a short link 32 with an arcuate lever 33. Preferably lever 33 in the form of a pair of spaced apart arcuate plates 34 provided with a series of openings 35, the upper end or" link 32 being inserted between plates 34 and pivotally attached by means of a cross bolt 36. One end of arcuate lever 33 is iulcrinned at 37 in a bracket 38 attached to the side wall 20. The other end of lever 33 is vertically movable in a guide bracket 39. A. vertically extending link or operating rod 40 has a yoke 41 at its lower end enclosing the lever 33 and pivoted thereto by means of a cross bolt, such as 36. The link 10 may be attached to the arcuate lever 33 by the same pivot bolt 35 as is used to connect the shorter link 32, or separate pivot bolts may be used in case the link 2 is to be connected to lever 33 at a point nearer its fulcrum 37 so as to decrease the amplitude of swinging movement of eat 5. The rod or link ll) is formed in two e 2 overlapping sections connected by bolts 42 pass ing through selected openings 43, whereby the effective length of link so may be varied.

A bell-crank comprising a pair of similar side plates 44.- is fulcrumed on a bolt 45 mounted in brackets l6 supported on the overhead beam r frame member 24. A spacing member 4'? surrounding e5 separates the two side plates 44. A swinging block as is pivoted between the lower arns 49 of the bell crank, and a yoke 56 at the upper end or link so i pivoted to block 48 by means of pin 51 so that the link 4o can swing in a direction longitudinally of the table and at right angles to the swinging movement or" hell crank as. An adjusting belt or rod 52 has an eye 53 at its inner end pivoted on a bolt 54 extending through the upper arms 55 of the bell crank. Rod 52 extends out through opening in the side frame 56 and also through an opening in a bracket 5? mount-e on beam a pair of adjusti g nuts 58 being threaded on rod 52 at the respective sides bracket 5?. It will be noted that the gate and the operating mechanism therefor, including link or fulcrum for the upper end of link 40 is carried by a fixed portion of the frame work and does not partake of the vertical and longitudinal reciprocating motions of table 1. With the apparatus in operation, the table and thegate opening 21 will move between the solid and dotted line positions, as shown in Fig. 3, and the pivoted end 27 of gate 25 will partake of this movement. However, the opposite end of gate 25 is connected through the links 32 and 40 and arcuate lever 33 with the fixed frame work 24, so that the free end 31 of gate 25 will be moved up and down slightly relative to the table and the gate opening 21, as the table is reciprocated This continual relative movement between gate 25 and the table serves to agitate the material back of the gate opening and will usually serve to prevent the larger pieces of material from becoming clogged in the openin Also the gate 25 is provided with a moderately sharp cutting edge 26, so that any pieces or" material that do become clogged in the opening will be cut down or split, thus keeping the opening clear. The tapered line of discharge, due to the fact that the gate has a greater swinging movement at one end than the other, also tends to loosen up any clogged material and release it from the opening. It will be noted that the gates, and the supporting and operating mechanisms associated therewith, are made of standard form with provisions for adjustment to the openings of different height than are required at spaced intervals longitudinally of the separating table.

In a copending application Serial No. M3582, filed of even date herewith, is disclosed and clari ied an improved system of riifles whereby the larger coal masses are supported by the rifiies instead of by the surface of the zoning deck, thus providing additional means for keeping the larger coal masses away from the outlet openings and facilitating the progress of the coal longitudinally of the table. The self-clearing gates disclosed and claimed in this present application are particularly adapted for use with the improved separating table disclosed in said copending application, but may also be used effectively with any air-cleaning system of the type referred to.

I claim:

1. In an apparatus for aircleaning coal or similar material, in combination with a cleaning table and means for imparting combined. vertical and longitudinal reciprocating movements to the table, there being a gate opening at one side of the table for expelling from the table, a gate for partially closing the opening pivotally mounted on the table adjacent one end of the opening and a substantially vertically extending link connecting the free end of the gate with a stationary member.

2. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning tabio and means for imparting combined vertical and longitudinal reciprocating movements to the table, there being a gate opening at one side of the table for expelling material from the table, a gate for partially closing the opening pivotally mounted on the table adjacent one end of the opening and means for automactially reciproeating the other end of the gate vertically with respect to the table as the table is reciprocated.

3. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table and means for imparting combined vertical and longitudinal reciprocatng movements to the table, there being a gate opening at one side 01 the table for expelling material from the table, a gate for partially closing the opening pivotally mounted on the table adjacent one end of the opening, means for automatically reciprocating the other end of the gate vertically with respect to the table as the table is reciprocated and means for adjusting the amplitude of'this vertical movement.

4. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table and means for imparting combined vertical and longitudinal reciprocating movements to the table, there being a gate opening at one side of the table for expelling material from the table, a gate for the opening pivotally mounted at one end of the table, a substantially vertically hanging link pivotally mounted at its upper end on a fixed member and adjustable means for connecting the lower end of the link with the free end of the gate whereby the amplitude of movement of the gate may be varied.

5. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table and means for imparting combined vertical and longitudinal reciprocating movements to the table, there being a gate opening at one side of the table for expelling material from the table, a gate for the opening pivotally mounted at one end on the table, a substantially vertically hanging link pivotally mounted at its upper end on a fixed member, an arcuate lever pivoted at one end on the table and pivotally connected with the lower end of the vertical link, and a second link pivoted at its lower end to the free end of the gate and adapted to be pivotally connected at its upper end with any one of a series of pivot points on the arcuate lever.

6. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table, means for imparting combined vertical and longitudinal reciprocating movements to the table, the table including upright side walls one of which is provided with a plurality of gate openings through which material is expelled, a gate for each of the gate openings provided with a lower cutting edge, and means for automatically reciprocating the gate vertically with respect to the upper portion of the opening as the table is reciprocated.

7. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table, means for imparting combined vertical and longitudinal reciprocating movements to the table, the table including upright side walls one of which is provided with a plurality of gate openings through which material is expelled, a gate for each of the gate openings provided with a lower cutting edge, the gate being pivotally mounted at one end within the side wall for swinging movement across the inner upper portion of the gate opening and means for moving the gate vertically as the table reciprocates.

8. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table, means for imparting combined vertical and longitudinal reciprocating movements to the table, the table including upright side walls one of which is provided with a plurality of gate openings through which material is expelled, a gate for each of the gate openings provided with a lower cutting edge, the gate being pivotally mounted at one end within the side wall for swinging movement across the inner upper portion of the gate opening, and means for adjusting the amplitude of this vertical movement.

9. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table, means for imparting combined vertical and longitudinal reciprocating movements to the table, the table including upright side walls one of which is provided with a plurality of gate openings through which material is expelled, a fixed framework above the table, and flexible curtains connecting the side walls of the table with the framework so as to enclose the separating chamber above the table, a gate for each gate opening pivoted at one end adjacent the openings within the side walls, a vertically hanging link connected at its lower end with the free end of the gate, a vertically swinging bell-crank mounted on the fixed framework within the separating chamber, the vertical link being pivotally supported at its upper end from one arm of the bellcrank, an adjusting rod connected with the other arm of the bellcrank and extending outside the separating chamber, and means engaging the outer end of the rod for adjusting the position of the bellcrank.

lO. In an apparatus for air-cleaning coal or similar material, in combination with a cleaning table, means for imparting combined vertical and longitudinal reciprocating movements to the table, the table including upright side walls one of which is provided with a plurality of gate openings through which material is expelled, a fixed framework above the table, and flexible curtains connecting the side walls of the table with the framework so as to enclose the separating chamber above the table, a gate for each gate opening pivoted at one end adjacent the openings within the side walls, a vertically swinging bellcrank fulcrumed on the fixed framework within the separating chamber, a vertical link pivotally supported from one arm of the bellcrank, an adjusting rod connected with the other arm of the bellcrank and extending outside the separating chamber, means engaging the outer end of the rod for adjusting the position of the bellcrank, an arcuate lever pivotally mounted on the table, the vertical link being connected at its lower end with the free end portion of the arcuate lever, and a second link pivotally connecting the free end of the gate with a selected point on the arcuate lever.

ANDREWS ALLEN. 

